Code result
B0278
HVAC Defrost Door Circuit
Moderate severity
What it means
A fault is detected in the HVAC defrost door actuator circuit; defrost airflow may not engage.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Defrost actuator failed
highOne of the most commonly reported causes for this code — check this first.
Related help
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